Two flutes, solid carbide. Mortise style bits have 1/4" upcut on end.D = Diameter; CL = Cutting Length; R = Radius; SH = Shank Diameter; OL = Overall Length, * = Mortise Style - 1/4" up cut on end.Note: Products labeled "Ships Direct from Manufacturer" are shipped directly from the manufacturer, whose warranty supercedes any offered by Woodcraft. In-stock product will ship within 5 business days. All returns after 30 days are subject to a 25% restocking fee. For details, click on the "Ships Direct From Manufacturer" link below.